Handwriting evidence evaluation based on the shape of characters: application of multivariate likelihood ratios

A novel Bayesian methodology has been developed to quantitatively assess handwriting evidence by means of a likelihood ratio (LR) designed for multivariate data. This methodology is presented and its applicability is shown through a simulated case of a threatening anonymous text where a suspect is apprehended. The shape of handwritten characters a, d, o, and q of the threatening text was compared with characters of the true writer, and then with two other writers, one with similar and one with dissimilar characters shape compared to the true writer. In each of these three situations, 100 draws of characters were made and the resulting distributions of LR were established to consider the natural handwriting variation. LR values supported the correct hypothesis in every case. This original Bayesian methodology provides a coherent and rigorous tool for the assessment of handwriting evidence, contributing undoubtedly to integrate the field of handwriting examination into science.     

Initials: A question of identity

It has been a generally accepted practice among document examiners to request known handwriting standards which duplicate the questioned material under examination.When initials are questioned it is not always possible to have initials duplicated and known signatures are sometimes substituted.A research study was conducted using a sample of 65 writers to determine if the letters in a group of initials were written in the same manner as the capital letters in a signature. The study showed that 69% of the writers in the sample made one or more changes or additions to their initials which were not present when they wrote their signatures.     

Informal politics: the role of Congressional letters in legislative behaviour and careers

Members of the United States Congress are cross-pressured by constituents, party leaders, the president, and even by their own career goals. Yet, they are limited in their time and resources, and must maximise the tools available to them. Given that Congressional letter writing to the president as a tool available to all members occurs so widely, such behaviour informs a deeper understanding of how legislators seek to professionalise as politicians in competitive national politics. Utilising a data set of nearly 13,000 Congressional letters across eight Congresses, the author finds that letter writers systematically differ from non-letter writers, shedding light on the value of letter writing in Congressional behaviour and career aspirations, as well as the drivers behind this form of behaviour. Letter content varies based on the institutional and individual characteristics of the letter writer, suggesting members differ in how they view and use this tool.     

Simulation Detection in Handwritten Documents by Forensic Document Examiners

This study documents the results of a controlled experiment designed to quantify the abilities of forensic document examiners (FDEs) and laypersons to detect simulations in handwritten documents. Nineteen professional FDEs and 26 laypersons (typical of a jury pool) were asked to inspect test packages that contained six (6) known handwritten documents written by the same person and two (2) questioned handwritten documents. Each questioned document was either written by the person who wrote the known documents, or written by a different person who tried to simulate the writing of the person who wrote the known document. The error rates of the FDEs were smaller than those of the laypersons when detecting simulations in the questioned documents. Among other findings, the FDEs never labeled a questioned document that was written by the same person who wrote the known documents as “simulation.” There was a significant statistical difference between the responses of the FDEs and layperson for documents without simulations.     

A statistical approach to aid examiners in the forensic analysis of handwriting

We develop a statistical approach to model handwriting that accommodates all styles of writing (cursive, print, connected print). The goal is to compute a posterior probability of writership of a questioned document given a closed set of candidate writers. Such probabilistic statements can support examiner conclusions and enable a quantitative forensic evaluation of handwritten documents. Writing is treated as a sequence of disjoint graphical structures, which are extracted using an automated and open-source process. The graphs are grouped based on the similarity of their shapes through a K-means clustering template. A person's writing pattern can be characterized by the rate at which graphs are emitted to each cluster. The cluster memberships serve as data for a Bayesian hierarchical model with a mixture component. The rate of mixing between two parameters in the hierarchy indicates writing style.     

The influence of right or left handedness on the ability to simulate handwritten signatures and some elements of signatures: A study of Arabic writers

It has been widely assumed since the 1970s that right-handed writers, on average, do not write or simulate handwriting any better than left-handed writers. This study has dug deeper into that question, to find narrow language environments which left-handed and right-handed writers simulate with different degrees of success or making different types of errors. These might provide useful markers of handedness in writers or forgers. The sample of 823 native Arabic-writing adults, 763 right handed and 60 left handed, first attempted to simulate two Arabic signatures. As expected, the accuracy of the simulations of the two groups was not significantly different. Simulation accuracy of a variety of narrower elements was then measured to search for small environments in which the two groups performed differently. Two elements – slant and alignment – were significantly more poorly simulated by left-handed subjects than right-handed subjects, although the differences were not great enough to be useful in suggesting the handedness of a forger. These differences in simulation accuracy were not totally explored or explained. Instead, the differences in types of errors to slant and to alignment were investigated. Left-handed simulators, but not right-handed simulators, showed a strong tendency that had been predicted for both groups: to slant strokes and letters toward the side of the writing hand, when the target strokes and letters slanted in the opposite direction. The difference between the handedness groups was great enough that a strong preference for leftward slant in an Arabic writer or forger might suggest left handedness, but not, of course, rule out right handedness. Right-handed simulators, but not left-handed simulators, showed a strong tendency that had also been predicted for both groups: for the line of writing to be higher on the side where the writing hand was located. Again, the difference between handedness groups was great enough that a strong tendency for the writing line to fall to the left in Arabic writing and simulation might suggest right handedness, but would certainly not rule out left handedness. Thus, suggestive, but not absolute, markers of handedness have been found. In an effort to explain these almost mirror-image patterns, it was noticed that the operation of two more tendencies, in addition to the operation in both groups of the two predicted tendencies, might explain the patterns of the data. If we assume that both handedness groups tended to slant toward the writing hand and tended to make the writing line higher on the side of the writing hand, the two other tendencies operating in both groups would have been a tendency to slant strokes and letters toward the end of the writing line, and a tendency for writing to fall toward the end of the writing line. The operation of these four tendencies would account quite well for the right-handed and left-handed patterns in the two groups.     

The probative character of Forensic Handwriting Examiners' identification and elimination opinions on questioned signatures

This 5-year study investigated the character of Forensic Handwriting Examiners' (FHEs) authorship opinions on questioned signatures through the medium of blind validation trials. Twenty-nine thousand eight hundred and eleven authorship opinions were expressed by FHEs on trial kits comprising randomized questioned genuine signatures (written by the specimen writer), disguised signatures (written by the specimen writer) and simulated signatures (not written by the specimen writer). Results showed that, as a group, FHEs were significantly more confident at identifying writers' genuine signatures than identifying writers' disguised signatures or eliminating specimen writers from having authored simulated signatures. It is proposed that the difference in FHE confidence arises from the difficulty they have in deciding which alternative authorship explanation accounts for perceived combinations of similar and dissimilar features between specimen and questioned signatures.     

The probative character of Forensic Handwriting Examiners’ identification and elimination opinions on questioned signatures

This 5-year study investigated the character of Forensic Handwriting Examiners’ (FHEs) authorship opinions on questioned signatures through the medium of blind validation trials. Twenty-nine thousand eight hundred and eleven authorship opinions were expressed by FHEs on trial kits comprising randomized questioned genuine signatures (written by the specimen writer), disguised signatures (written by the specimen writer) and simulated signatures (not written by the specimen writer). Results showed that, as a group, FHEs were significantly more confident at identifying writers’ genuine signatures than identifying writers’ disguised signatures or eliminating specimen writers from having authored simulated signatures. It is proposed that the difference in FHE confidence arises from the difficulty they have in deciding which alternative authorship explanation accounts for perceived combinations of similar and dissimilar features between specimen and questioned signatures.     

An esoteric technique useful in the identification of unidentified remains from the examination of faded,illegible hospital identification wristbands

A technique routinely used in the examination of questioned documents has been found to be of assistance when employed in the examination of faded and/or partially legible hospital identification wristbands found with unidentified remains (UIDs). A non-destructive test used predominately by forensic document examiners in the analysis of writing inks, handwritten alterations, and obliterations has proven useful throughout the years when confronted with this unusual type of documentary evidence. This discussion paper was prompted by the Tri-State Crematory disaster, Walker County, Georgia, from a request by investigators as to whether or not any information could be obtained from the examination of faded hospital identification wristbands where no information was readily discernable. Subsequent analysis by non-destructive infrared inspection, a standard technique used in the examination of questioned documents, proved useful in assisting with the identification of unidentified skeletal remains.     

Relative Width and Height of Handwritten Letter

This is an exploratory study that analyzes the width and the height of letters in two texts written by each of the 21 writers analyzed. After detrending the linear, text, and allograph trends, we proceeded to comparing the sizes obtained in different texts. The different detrended series were compared by means of correlation and t‐test. According to the results regarding the width of letters, the texts of 19 of 21 writers correlated strongly, whereas the texts of two writers did not correlate with the limits of the threshold. With regard to the height of letters, texts written by between 18 and 21 writers of 21 writers correlated strongly, whereas texts that did not correlate were within the threshold value. Regarding both the width and the height of letters, of 21 writers, texts written by between 19 and 21 individuals were found to correlate strongly.     

中国现代文学的“因缘”因素：以张爱玲为例

因缘是佛教与中国传统文化相融合的产物.张爱玲等人的因缘写作,一是源于因缘为中国人的文化心理结构,二是源于明清小说对世俗化因缘的描绘.文化心理的变动制约着现代作家的因缘写作.因缘在现代作家笔下具有多种含义,其叙事格局也有摆脱佛教影响的倾向.就因缘叙述所具备的现代特性而言,启蒙作家是完成的现代性,张爱玲等人是未完成的现代性,是一种融合有传统的现代性.     

浅谈左手书写者左右手笔迹的特点及变化规律

目的为左手书写者左手笔迹及右手笔迹的检验鉴定提供参考依据。方法收集左手书写者的左手正常笔迹和其右手笔迹,进行比对检验和实验数据统计分析。探讨左手书写者左手笔迹和右手笔迹的特点及变化规律。将左手书写者的左、右手笔迹的特点和变化规律与右手书写者的右、左手笔迹的特点和变化规律进行比较。结果左手书写者的左手笔迹和右手笔迹在笔顺、写法、错别字等特征上保持稳定。结论左手书写者的笔迹检验应结合其左手笔迹和右手笔迹的特点和变化规律,并注意其与右手书写者的右手笔迹和左手笔迹的特点和变化规律的区别与联系。     

Brain function and writing with the unaccustomed left hand

Twenty right-handed subjects were asked to handprint a passage containing all the letters of the alphabet once with each hand. The purpose was to describe the changes a document examiner can expect to find in handprinting done with the unaccustomed left hand and to offer a hypothesis as to why these changes occur. It was found that many of the writers displayed persistent differences between their right- and left-hand writings. It is suggested that these differences were due to both a lack of manual dexterity when writing with the unaccustomed left hand and to the fact that different neurophysiological processes are involved.     

The anonymous letter writer--a psychological profile?

Anonymous letters fall into many categories--threats, obscene messages, racial slurs, extortion demands, guilty conscience statements, stool pigeon letters, robbery or burglary notes, and so forth. These are examined by the document examiner for any information that may lead to the identity of the writer. Such examinations involve unusual aspects of paper or envelopes, watermarks, detection of indented impressions, and so on, and also a comparison with previous anonymous submissions. Several cases will be discussed where, additionally, psychological profiles of the writer were produced by a psychiatrist and a psychologist, based upon the content of the letters.     

DNA Analysis and Document Examination: The Impact of Each Technique on Respective Analyses

Threatening letters, counterfeit documents, and anonymous notes can commonly be encountered in criminal situations. Such handwritten documents may encourage DNA to transfer from the writer's hands and lower arms when these areas come into contact with the document. As any DNA transferred is likely to be at a low level, sensitive low copy number (LCN) DNA analysis can be employed for testing document exhibits. In this study, we determine locations on the document that are most commonly touched during writing and handling and compare DNA recovery from these sites. We describe the impact of DNA sampling on subsequent document examination techniques including the ESDA^® and likewise the effect of the ESDA^® and two other document examination techniques on subsequent DNA analysis. The findings from this study suggest that DNA results can be obtained through targeted sampling of document evidence, but that care is required when ordering these examination strategies.     

Determining Line-Crossing Sequences Between Laser Printing and Writing Pen Using Coaxial Light

Determining the application sequence of hand-written pen ink and printer toner lines has attracted significant interest in questioned document examination. This study uses coaxial light to determine line-crossing sequences, with intersections observed under a VSC600 forensic document workstation and a Leica M205A Stereo-microscope. Results show that reflected light at intersections and color contrast between intersections and nonintersections was observed when a hand-written ink line passes over a toner line, while a toner line passing over a written line appeared dull, with no color contrast. The procedure was tested under a range of conditions, such as types of writing pens and laser printers, the writer, and writing pressure, with the latter playing an important role in the evaluation. To validate the results, a 90% detection rate and 98% accuracy rate were achieved from 50 samples of blind testing, which is more effective than optical microscopy.     

Generational discourse in urban youth images

The history of generations is often researched in the light of ego-documents, including diaries or letters. These sources of communication between young and old require methods of literary criticism, as this article suggests in exemplary cases. Popular (and in some cases popular forms of learned) literature show how stereotypes dominated letters between Nuremberg fathers and sons fom the 16th century. Reading these letters as witnesses of direct emotional expression, as has been done so far, would be problematic on a theoretical level of the concept of autobiography (according the Ricoeur ‘an other’ of the self), but also an empirical level. Letters were cultural artefacts that were considered well-formed only when they met the standards set by the urban youth image. This included a conglomerate of religious discourses, psychological assumption about the nature of emotions, the urban system of values and honour relating to merchant education more specifically. In letters of this intergenerational context, even information could be put into the context of a situational self-representation of the person writing. Writing a letter as an apprentice or a student was not at all confined to convey factual information. Rather than that, writing letters meant to participate in the generation of norms and to act on a meta-level of communication, as well. Negative images of youth were rhetorically implemented in letters to maintain and reaffirm the hierarchy within the family. Letter exchanges secured economic stability of family firms and the subsequent social rise.     

Generational discourse in urban youth images: Private letters and popular literature in the case of Nuremberg's Tucher family around 1550

The history of generations is often researched in the light of ego-documents, including diaries or letters. These sources of communication between young and old require methods of literary criticism, as this article suggests in exemplary cases. Popular (and in some cases popular forms of learned) literature show how stereotypes dominated letters between Nuremberg fathers and sons fom the 16th century. Reading these letters as witnesses of direct emotional expression, as has been done so far, would be problematic on a theoretical level of the concept of autobiography (according the Ricoeur ‘an other’ of the self), but also an empirical level. Letters were cultural artefacts that were considered well-formed only when they met the standards set by the urban youth image. This included a conglomerate of religious discourses, psychological assumption about the nature of emotions, the urban system of values and honour relating to merchant education more specifically. In letters of this intergenerational context, even information could be put into the context of a situational self-representation of the person writing. Writing a letter as an apprentice or a student was not at all confined to convey factual information. Rather than that, writing letters meant to participate in the generation of norms and to act on a meta-level of communication, as well. Negative images of youth were rhetorically implemented in letters to maintain and reaffirm the hierarchy within the family. Letter exchanges secured economic stability of family firms and the subsequent social rise.